t1 = ('aa', 'bb', 'cc', 'bb')
# t1[0] = 'aaa' # 报错

# 元组里的列表可以修改，尽可能不要去修改元组内容
t2 = ('aa', 'bb', ['cc', 'dd'])
print(t2[2]) # ['cc', 'dd']
print(t2[2][0]) # cc
t2[2][0] = 'Tom'
print(t2) # ('aa', 'bb', ['Tom', 'dd'])